Ventilator



Jan. 18, 1966 H. PAPST 3,229,897

VENT ILATOR Filed Jan. l0, 1964 Herma/1f, Par/arf United States Patent O 3,229,897 VENTILATOR Hermann Papst, St. Georgen, Black Forest, Germany Filed Jan. 10, 1964, Ser. No. 336,975 Claims priority, application Germany, Jan. 14, 1963,

30,937 4 Claims. (Cl. 230-117) The present invention relates to ventilators, especially to such types of ventilators that are used for cooling electric apparatus. For this purpose numerous types of Ventilators have already become known.

It is a main object of this invention to obtain without considerable additional costs by a novel design special advantages in regard to quick and easy assemblage.

It is another object of this invention to provide an electric ventilator of high efficiency and which runs very quietly.

It is a further object of the invention to provide a ventilator which may be easily adapted to various types of electric apparatus.

It is a still further object of this invention to provide an arrangement of the type mentioned which is comparatively simple in its structure and reliable in operation.

With above objects in view the ventilator, according to the invention, comprises a housing provided with spokes and a central portion supported on the spokes, and a motor with external rotor having fan blades on its outside, said motor being mounted on a flanged pipe which is fixed to the central portion of said housing by an easily detachable connection, whereas the stator of said motor is situated on the outside lof the flanged pipe, and the radial bearings as well as an axial bearing of the shaft of said rotor being arranged within said flanged pipe.

In a preferred embodiment of the invention, the axial bearing is clamped in between the flange of the flanged pipe and the central portion of the housing, preferably by screws.

Furthermore the axial bearing may be arranged to form together with the central portion of the housing and the flange of the pipe an oil-proof sealing for the bearings.

In certain cases it is advantageous to provide the bellshaped rotor housing with fan blades on its outside and a ring of hysteresis material on its inside.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation together with additional objects and advantages thereof, will be best understood from the following description of a specific embodiment when read in connection with the accompanying drawing, in which corresponding parts are marked in all figures with the same numbers and in which:

FIG. l is a sectional view of the ventilator taken along line A-B of FIG. 2,

FIG. 2 is a partial elevated view of the ventilator,

FIG. 3 is a sectional view of the ventilator wheel and its shaft,

FIG. 4 is an elevated view of the stator of the motor,

FIG. 5 is a sectional View of parts of the axial bearing,

FIG. 6 is a sectional view of the assembled motor, the external rotor carrying fan blades,

FIG. 7 is a sectional view of the ventilator housing,

FIG. 8 is a partly sectional view of means for fixing the motor within the ventilator housing,

FIG. 9 is a sectional view of a spring for fixing the filter,

FIG. 10 is a fragmentary view of a detail,

FIG. 11 is a sectional view of a modification of the ventilator wheel.

3,229,897 Patented Jan. 18, 1966 ICC FIGS. 38 are illustrated in a reduced scale.

Referring now to the drawings, and more specifically to FIGS. 1 and 2 of the same, it will be seen that the ventilator according to the present invention comprises a housing 1 having supporting spokes 2 for a central portion 3. Stator 4 with winding, protected by an insulating cover 5, is mounted on a flanged pipe 6, which serves as support. This flanged pipe contains on the inside two radial bearings 7 in which shaft 8 rotates together with hub 9, rotor 11 and attached blades 12. T-he rotor and the stator are assembled separately by fixing the bearing rings 13, 14 on shaft 8 by means of a snap ring 15.

This construction offers the advantage that the motor can separately be inspected, measured and tested with high tension. Especially it is possible to balance the rotor after assembly so that even small asymmetries caused by magnetic forces can be compensated.

Furthermore, stator 4 together with bearing housing 6 and bearings 7 can separately be ground by means of a center pin, so that in a simple manner very high accuracy may be obtained. Motors of such an embodiment run without the well-known humming noise. Flange 16 of stator bearing 6 is fixed by screws 17 to the central portion 3 of ventilator housing 1.

If it is desirable, a flange cover 3 may be inserted into the central portion 3 according to FIG. 8.

As the motor with its external rotor represents a complete unit, it may therefore be combined with various housing types respectively supporting arms. In this way an extend application is obtained together with a simplification of the storage problem and an improvement of the manufacture of the motor by reducing the number of different types. Furthermore it is a considerable advantage, that when using such ventilators only a stator or eventually the motor has to be kept on stock as spare parts. As the reliability of electronic units requires high safety, it is of great importance to maintain the security of operation of the auxiliary devices that is to say of the ventilators.

The lower part of FIG. 1 is a section B through a corner of the housing. By means of sloping corner walls 20 housing 1 is enlarged on both sides to a square profile. Thus the blower is considerably improved in regard to air pressure and amount of air flow but the size and dimensions of the blower do not exceed the square closely surrounding the diameter of the ventilator wheel. Furthermore in the filter, the free space for the air is enlarged.

In the embodiment of the invention, illustrated in FIGS. 1, 2, 9 and 10 the fixing means of the ventilator are used also to fix the protection grid.

Mounting the ventilator is simplified by the fact that it is sufficient to cut only a square opening in the supporting wall. Housing 1 is fixed by screws 23 to wall 22 of an electric apparatus which is not shown in detail. A square hole in wall 22 is sufficient as the screws in the corners can be tightened owing to the supporting effect of frame 24 of protection grid 25. The protection grid and its frame may be fixed on either side of the ventilator. If necessary, also a filter 26 with protection grid 27 and additional frame 28 can be simply attached and fixed by means of springs 29. The springs, the protection grid and its frame are fixed and tensioned by means of screws 23. The tensioned springs are acting diagonally in outward direction against the corners of frame 28. In this way frame 28 is mounted under tension and therefore the filter frame will always fit well along its edges.

Frame 28 can be made of weak material as cheap, s0- called throw-away piece without the danger of losing its correct shape. Screw 23 keeps spring 29 in a stamped corner of frame 24 and prevents said spring from being twisted. This can be seen more detailed in FIGS. 9 and l0.

FIG. 3 shows the ventilator wheel respectively the rotor with its fan blades before being mounted into stator 4, shown i-n FIG, 4. These parts are connected by means of bearing rings 13 and 14 and snap ring 15, shown in FIG. 5.f The complete motor-ventilator is then inserted into the ventilator housing shown in FIG. 7 and is xed there by means of flange cover 3 and screws 17; ange 3 being clamped in between ange 16 and flange cover 3. A cover 18 forming a thrust bearing is mounted between flange 16 and the central portion 3, respectively 3 of the housing.

By this arrangement all wishes of consumers and manufacturers are met well and at a favourable price.

A ventilator according to the invention with outstanding efficiency is obtained by providing the rotor with a ring 11' of hysteresis material (see FIG. 11) instead of a cage. By this, under equal conditions, the number of revolutions of the rotor and its diameter will be increased and, besides that, the bell shaped ventilator cover is reduced and thus the cross section of the outlet for the air is enlarged.

Instead of using a ring of hysteresis material, it may be advantageous in some cases to use a ring of soft iron which is, at least at one side, provided with a copper ring in order to improve its conductivity. The number of revolutions may be increased by reducing the cross section of the iron ring by means of external cuts at a distance equal to that of the poles.

While the invention has been illustrated and described as embodied in a special arrangement it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any Way from the spirit of the present invention.

What is claimed and desired to be secured by Letters Patent is:

1. A ventilator comprising, in combination, a housing `having a plurality of substantially radially extending spokes and a central portion supported on said spokes; a tubular member having a flange at one end abutting against said central portion of said housing; releasable .connecting means connecting said ange to said central portion of said housing; a cover extending transversely vover said oneend of said tubular member and partly over said flange thereof and being clamped by said connecting means between said flange and said central portion of said housing; axially spaced Vbearing means supported in said VYtubular member; stator means fixed to the outer surface `of said :tubular member and projecting radially therefrom; a shaft turnably mounted in said bearing means and projecting with one end thereof beyond the other .end of said tubular member, the other end of said shaft engaging said cover Vso that the latter forms a thrust bearing for said shaft; and rotor meanssurrounding said stator means, said rotor means having a transverse portion fixed to said one end of said shaft for rotation therewith and a plurality of fan blades substantially radially projecting from the outer peripheral surface of said rotor means.

2. A ventilator comprising, in combination, a housing having a plurality of substantially radially extending spokes and a central portion supported on said spokes; a tubular member having a flange at one end abutting -against said central portion of said housing; releasable connecting means connecting said flange to said central portion of said housing; a cover extending transversely over said one end of said tubular member and partly over said vflange thereof and being clamped by said connecting means between said flange and said central portion of .said housing, said cover forming an oil-proof seal at said one end of said tubular member; axially spaced bearing means supported in said tubular member; stator means -xed to the outer surface of said tubular member and -projecting radially therefrom; a shaft turnably mounted in said bearing means and projecting with one end thereof beyond the other end of said tubular member, the other end of said shaft engaging said cover so that the latter forms a thrust bearing for said shaft; and rotor means surrounding said stator means, said rotor means having a transverse portion fixed to said one end of said shaft for rotation therewith and a plurality of fan blades substantially radially projecting from the outer peripheral surface of said rotor means.

3. A ventilator comprising, in combination, a housing having a plurality of substantially radially extending spokes and a central portion supported on said spokes, said spokes being shaped as guide vanes; a tubular member having a ange at one end abutting against said central portion of said housing; releasable connecting means connecting said flange to said central portion of said housing; axially spaced bearing means supported in said tubular member; stator means xed to the outer surface of said tubular member an-d projecting radially therefrom; a shaft turnably mounted in said bearing means and projecting with one end thereof beyond the other end of said tubular member; rotor means surrounding said stator means, said rotor means having a transverse portion fixed to said one Vend of said shaft for rotation there- With and a plurality of fan blades substantially radially projecting from the outer peripheral surface of said rotor means; and a cover clamped between said ange and said central portion of said housing, said cover having a portion extending into said one end of said tubular member and being formed with a cavity engaged by the other end of said shaft so that said cover forms a thrust bearing for said shaft.

4. A ventilator comprising, in combination, a housing having a plurality of substantially radially extending spokes and a central portion supported on said spokes; a tubular member having a flange at one end abutting against said central portion of said housing; releasable connecting means connecting said ange to said central portion of said housing; axially spaced bearing means supported in said tubular member; stator means fixed to the outer surface of said tubular member and projecting radially therefrom; a shaft turnably mounted in said bearing means and projecting with one end thereof beyond the other end of said tubular member; rotor means including a cup-shaped member having a transverse por- -tion xed to said one end of said shaft and an annular portion surrounding said stator means radially spaced therefrom, a ring of hysteresis material fixed to the inner surface of said annular portion, and a plurality of fan blades radially projecting from the outer peripheral surface of said annular portion; and a cover clamped between said flange and said central portion of said housing, said cover having a portion extending into said one end of said tubular member and being formed with a cavity engaged by the other end of saidshaft so that said cover forms a thrust bearing for said shaft.

References Cited by the Examiner UNITED STATES PATENTS 2,742,223 4/1956 Font 230-117 2,855,141 l0/l958 Van Rijn 230-117 2,926,838 3/1960 Van Rijn 230-117 2,990,112 6/1961 Levy et al. 310-67 X 3,002,118 9/1961 Papst 310-67 X 3,058,651 10/1962 Mobley 230-117 X FOREIGN PATENTS 1,053,645 4/ 1959 Germany.

ROBERT M. WALKER, Primary Examiner.

LAURENCE V. EFNER, Examiner. 

1. A VENTILATOR COMPRISING, IN COMBINATION, A HOUSING HAVING A PLURALITY OF SUBSTANTIALLY RADIALLY EXENDING SPOKES AND A CENTRAL PORTION SUPPORTED ON SAID SPOKES; A TUBULAR MEMBER HAVING A FLANGE AT ONE END ABUTTING AGAINST SAID CENTRAL PORTION OF SAID HOUSING; RELEASABLE CONNECTING MEANS CONNECTING SAID FLANGE TO SAID CENTRAL PORTION OF SAID HOUSING; A COVER EXTENDING TRANSVERSELY OVER SAID ONE END OF SAID TUBULAR MEMBER AND PARTLY OVER SAID FLANGE THEREOF AND BEING CLAMPED BY SAID CONNECTING MEANS BETWEEN SAID FLANGE AND SAID CENTRAL PORTION OF SAID HOUSING; AXIALLY SPACED BEARING MANS SUPPORTED IN SAID TUBULAR MEMBER; STATOR MEANS FIXED TO THE OUTER SURFACE OF SAID TUBULAR MEMBER AND PROJECTING RADIALLY THEREFROM; A SHAFT TURNABLY MOUNTED IN SAID BEARING MEANS AND PROJECTING WITH ONE END THEREOF BEYOND THE OTHER END OF SAID TUBULAR MEMBER, THE OTHER END OF SAID SHAFT ENGAGING SAID COVER SO THAT THE LATTER FORMS A THRUST BEARING FOR SAID SHAFT; AND ROTOR MEANS SURROUNDING SAID STATOR 